CA2803866A1 - Drying method for ceramic greenware - Google Patents

Abstract

The present invention is directed to a method comprising a) placing wet ceramic greenware body (36) on a carrying structure, and b) exposing the wet ceramic greenware body (36) to conditions such that the liquid carrier in the ceramic greenware body (36) is substantially removed; wherein the carrying structure contains a carrying sheet (28) comprising a material which, retains its shape under drying conditions, the carrying sheet (28) having two flat parallel faces and a plurality of walls (31) perpendicular to the flat parallel faces wherein the walls (31) form a plurality of flow passages (32) communicating between the two faces wherein the largest distance between any two walls (31) in the carrying sheet (28) is about 6 mm or less and the walls (31) have a sufficient thickness to support the wet ceramic greenware body (36) under drying conditions without deforming and the area of the flow passages (32) measured parallel to the two faces is from about 60 to about 90 percent by volume.

Description

DRYING METHOD FOR CERAMIC GREENWARE

CLAIM OF PRIORITY
[001 This appliccation claim priority from US Provisional Application & :Hal No, 61135K,487, filed June 2y, 2O1O, an. from US Prssvisiorml Application Serial No. 61/38O,802, filed September 1, 2010; both incol :orated herein by reference, FIELD OF INVENTION

[002] The present inveniiorl Iehrtes t a method of drying %vet Ceramic greenware bodies with impro'veÃl. productivity.

BACKGROUND
[OO31 Ceramic parts are generally prepared by forming a n:tixture of a cerana c prec,urso?t, a hinder and a liquid carrier, shaping to rn1xtIire into a near net sh a.pe. i'eInoving the liquid carrier.re'-I`"f,ov:int the: hinder and then 4:xpcrsir the remaiiacler of eat?rnp >Faesat to c unditif ms to form the ceramic stru Wrz,. 'I ; p dally the carat?'-tic str'ucture is formed by heating the ptvvursor to high teirrpe:F Itnr[: , in some Ã:awes irk the presence of a reactant. Removing the liquid carrier before removal of the binder and forinatiorr of the ceramic ::trarcture is necessary to allow the Subsequent steps to function as desired. A pI _ c-t d c ao i r i water. The shaped pari resulting l'mm the shaping step is referred to as greenware. Stresses are introduced into the gaeenwnarc during removal of the liquid carder. Such Ftres; .s can cause cracks in the greenw=acre: and the subsequent ceramic part.. One class of ceramic part for Which this process is owed are flow through filtei's, Flow through filters, generally comprise structure having-, two opl>osrn:; faces with channels or p Fo s as ;ew that extend frorrl I:+ne face to the other face. In one ei?alac?elinat:aat, ever.; other opening for the c:hdannelw or passages are plugged on one end and the Gathers are plugged on the other end. This means that for every channel all adjacent channels are plugged on the opposite erid, The p.ractiea1 i:naport, of this strraeturt:
is that when a fluid is introduced to one face of the filter it must .flow into the open channel` Gala that face and pass through the walls between the charmel to the adiacent charan4els to r ach the oppo\ite face.
Material s, such as solid paa'ticlew that are larger than the pores in the walls akr filtered- out of the fluid and retained on the introduction side of the %vazlls of the c:.hannelsr The presence of cracks or defect,, in the 'inal ceramic flaw through filter can allow particles. that the filter is designed to re:taa n. to pass trough the cracks and defects to the second face of the flow through filer thereby rendering the filter inneffecti.'ve. The step of removing Ãhe. liquid ca-frier cause's a significant }per certtage. of co tan-tic gre eriww are parts to crack or form Voids or defects.
(004] 'W" hat is needed is a method i:ior :removing the liquid carrier from wet ceramic greenwvaa_re wherein the occurrence of cracks, voids and defects are significantly reduced and are at a low level.

SUMMARY OF THE INVENTION

In one embodiment the present invention relates to a method comprising a) placing iw'et, ce rari:tic' gre errwvare body on: a carrying structure, and h.) exposing the wet ceramic greenwware body to conditions st-tch that the liquid carrier in the ceramic greenware boos is srtbs,tarltially removed; wherein the carrying ;stmctui Contains a carrying sheet comprising a Material Which retain, its shape unclei drying conditions, the carrying sheet heaving two girt parallel faces and a plurality of wills perpendicular to the flat parallel faces' wherein the walls form a plurality of flow passages communicating between the two faces s herein the largest di tance between any two walls in the carrying sheet is about 6 Ham or less and the walls have a sufficient thickness to siupport the wet ceramic ;reenware body under drying conditions without deforming and the area of the flow passages measured parallel to the two laces is from about 60 to about 90 percent by volume.

10051 In one embodiment, the, carrying structure comprises a carrying sheet having sufficient: f?ropc i ties and thickness to retain its shape, not deform, under liquid candles removal conditions. In another ernbod=_iment, the carrying structure comprises a caarry'in t gilt"it rS'hich is adapted to directl,, contact and support the %v et ceramic { i'eenware. body and a support plate which unctions to provide sufficient stiffness to the carrying structure so that the carrying structure: retains its, shape under liquid carrier removal cotielitioiera.
Preferably, the liquid carrier is removed by placin ; the wet ceramic g eenwvare body supported on the cai,.rying structure in an oven. Preferably, the liquid carrier is r moved by contacting the. wet ceramic greeinwware body' with a- drying .fluid or by exposing the wet ceramic g,reeri far'. body to a Vacuum, in one Preferred the wet ceramic greemware body is placed in an oven and a drying fluid. is contacted. with the wet ceramic greeriwaxe body or the wet ceramic greenware body is exposed to a vacuum. Preferably, the wet ceramic gveovware body supported on the c arT in l structure is placed in an ov n, either periodic (batch type) or belt driven (coatiriuous throughput) and contacted with a drying fluid or exposed to a vacuum %hile in the oven.
[008] It should be appreciated that the abo wee referenced embodimcents and eY
arnl>le s a are rrou lirz~itinfv, as others exist within the present invention, as shown and described herein. The rrtethocls of the invention result in a higher percentage of ceramic parts prepared which are crack, void and! or defect free.. This, results it-i a more efficient production method.

DESCRIPTION OF I' E DRAWINNIGS
[0071 Figure I is a conventional carrier stricture.
[008] Figure'-) is as cutaway vieev of the. con entional carrier structure f Figure 1. along line 2-2 wherein the view is along a plane perpendicular to the lace shown.
[009] Figu 3 is a view of a support plate. useful in a catrrie tructure.
(0010] Figure 4 is a cut away view of the carrier sheet located on the support sheet of th ea rierstructure of Figure 3 along; line 4-4 wherein the view is along a place perpendicular to the face shown.
[0011] figure 5 is a view of a second emhodinieni of a support plate of a:, carrier structure..
[0012] Figure 6 is a cut awa view of a carrier sheet located on the second embodiment of a support sheet of the carrier structure of Figure 5 alo.ti line 6-6 wherein the view is along a plane perpendicular to the face shown.

[0013] Figure 7 is, a view of the first embodiment of a carrier structure of the :invention from above the Barrier sheeà disposed on the support sheet.
[0014] Figure 8 is a view of the second embodiment of a carrier structure of the invention from above the carrier sheet disposed on the aipport sheet, [0015] Figure 9 is view of the first embodiment of the carrier structure of the invention located on a conveyor during the drying proces .
[0016] Figure 10 is vie"= of the second enihodi.ment of the carrier structure of the invention located on a Conveyor during the. drying process.
(0017] Figure 1 I illustrates an embodiment of a support sheet wherein an insert is used to create an air gap, (0018) Figure 12 is a cut away View of the support sheet of Figure 12 showing also the.
can-icr sheet disposed thereon.
[0019] Figure 13 is a side view of an e.:riihodim nt of a support star ture wherein the c aan ying sheet is supported on the peripheral raised section of the support sheet, DETAILED DESCRIPTION OF THE PREFERRED :M10D. ME NT
[OO2O] The explanations and illustrations presented heroin are intended to acquaint others skilled in the art with the invention, its principles, and its practical applacaatio.n. Those skilled In the art may adapt and apply the invention in its numerous frees, as may be best suited to the requirements of a particular aase:. Accordingly, the specific embodiments of the present invention as set forth are not intended as being exhaustive or limiting of the invention, The scope of the invention should , therefore, be. determined not with reference to the above.
description, but hould instead he determined with reference to the. appended claims, along with the full scope Of equivalents to Which such claims arc entitled. Other cctttt?inations are also possible as will be gleaned from the following clam , which are also hereby incorporated by reference into this written description, Each of the components introduced above will he further detailed in the paragraphs below and in descriptions of illustrative a- a mp ies/ tomb sdime.tt s..
[0021] The pre:aent invention as directed to a unique solution for removing the liquid carrier from wet ceramic. g e.nwaare bodies wherein a low p) rcentage of the resulting Ceramic bodies contain defects, p ferably the percentage of defective ceramic bodies is about 20 percent or less, more preferably 10 percent or less and 2 percent or less, Stated a_lte:rttttiv ely, the nneth;aod results in a high percentage of defect free ceramic bodies, preferably 8th percent or eater of detect free bodies, more preferably about 90 percent or greater of defect T'r'ee bodies aand most preferably about 98 percent or greater of defect free parts. Defect as used .herein means the ultimate (final) ceramic body contains a crack: or void which interferes ww ith function of the hsdy. For instance, where the ultimate ceramic body is desgne as a flow through filer a defect is a crack or void which pasxes particles through the walls of the Ceramic body which the ceramic body is intendd to filter o ut of a fluid suvam, that is the body does not main particles it is de signed to retain and atllows them to pass throu h walls of the body, [BO22 As used herein the term wet ceramic greei1 are means ceramtt c.
greenwaare containing; a sufficient amount of liquid carrier to be shapeable, Generally this means that the ;reenw are contains a 3ignrificant iitacttait.t dt:Ã' lidltaid d airier, forexample f i"om a bout 2.5 to about 35 percent by weight of the awet ceramic recnware.. Substantially removed is used in the context of retatovaà of the liquid carrier from the wet ceramic greens ware means that the gree:nwetc: can be subjected to removal of the hinder and formation of the ceramic strtactuae without the liquid carrier interfering in the process. In. this context, substantially removed means that about 10 percent by wweilht or less of liquid carrier is retained in the ceramic greenbiare body and more preferably aabout'2 percent by weight or less.

[OO23 Ceramic parts are i enerallyy prepared by contacting one or more Precursors for the ceramic structure, ceramic precursors, optionally' one or snore- binders and one or more liquid caarriers. The ceramic precursors are the reactants, or components which when exposed to certain Conditions form a ceramic body or part. Any k nownn ceramic pr'ecursor's may be utilised in the formation of wet ceramic K reenac aat e bodies and ultimately ceramic bodies derived front the method of the invention, Included in ceramic precursors are the precursors uttili.zed. to prepare mullite bodies (such as disclosed in US 7.485,594. 'S 6 953,554; US
4,948,766 and US 5,173,349 all incorporated herein by reference). silicon carbide bodies, cordierit bodies, aluminum titaanate bodies and the like. Binders useful in this rove ation include any known materials which tender the wet ceramic gre'enware shapeable.
Preferably, the hinders are organic materials that decompose: or burn at temperatures below the temper tture wherein the ceramic precursors react to forma ceramic l odies or part:s. Among preferred binders are those described in Introducrionn to the Principles o. t:
ara.rTeti' . ;?"o C.S.Stt'f43 , 1. Reed, 'iley lnte:rscience, 1988) incorporated herein by reference. A
particularly preferred binder is methyl cellulose (such as Mt.l;.`HOCEL A l 5L ' methyl cellulose.
The Do"A, Chemical co., Midland, Mich,), Liquid carriers include any liquid that facilitates formation of a shapeable sw`et cerarruc mixture. A long preferred liquid carriers (dtspe.rs asst are thcr;, e ta'raateri als described in lntrocf fiction to the Principles of Ceramic Processing, T. Reed, Wiley lnterscience, 1988), A particularly preferred liquid carrier is water, The mixture useful in preparing wet ceramic greenware bodies may be made by any suitable= method such a Is those known in the art, Examples include ball rnil:ting, ribbon blending, vertical screw mixing. V-blending and attrition millin 1. The mixture may be prepared dry (i.e., in the absence of a liquid carrier) or wet. Where the mixture is prepared in the absence of a liquid carrier, .+ liquid carrier is added subsequently utilizing any (if the methods des<ribed in this paragraph, [0024] The mixture of ceramic precursors, optionally hinders, and liquid carriers, ruz-ty tie shaped by arty means known in the yart, Examples include injection robins, extrusion, isostatic pressing, slip casting, roll compaction and tape caasting. Each of these is described in more detail in introduction to the Principles of Ceramic Processing, I. Recd, Chapters 20 and 21, Wiley .ante rscience, 1988, incorporated herein by reference. hi a preferred embodiment the mixture is Shaped into the near net shape and size tit the ultimate desired ceramic body, such as 'a flow through fillet, Near net shape arid size means the size of the wet ceramic gr>cnu%are body is within itt percent by volume of the size of the final ceramic body, and preferably the size and shape is within 5 percent by volume of the size of the final ceramic body. Preferably the wet octaarrlic green ware body does not have and of the channels or flow passages, blocked or plugged.

(0025] Ina preferred embodiment, the wet ceramic greeraware body is shaped such that it c ,m: be utilized as a flow through filter, At this stage in the process the wet ceramic gr enwm-e body has two opposing faces which are substantially planar, The wet ceramic *rec nwari body exhibits as cross sectional shape w Which is c onsisterit for all planes parallel to the two opposing faces, The cross sectional shape can he any shape which is suitable for the intended use. The shape may be irregular or mik be of any known shape, Preferably the cross-sectional shape is round, oval or polygonal. In one p'ef"Orree1 enkà odirrient, the shape is :round, oval or rectangular (including square), If the shape is it egular, it is p:referred that the shape have at least one surface that is planar such that the wet ceramic body can be disposed on the car-tying, sheet on the plasm-r swface. The wet ceramic greenware body has, it plurality of walls formed Which extend from one. Opposing face to the other opposing face, The walls form a plurality of flow passages that extend from one opposing face to the other opposing face.
Preferably, at this stage, all of the flow passages are. open to both opposing, laces. This allows more efficient removal of liquid carrier.
(0026] Thereafter the wet ceramic gIeenskarc body is subjected to conditions to remove the liquid c:akrr-ieeT, that is to dry the wet ceramic g-reenwa re body. Th :
stet ceramic grr ens ware body is placed on a ca rryirag structure while it i suÃ,fecteed to the liquid carrier removal conditions, The carrying structure performs the function of supporting the wet ceramic gre:e.nwart : body= through the liquid ca:trier removal process.
Additionally., the carrying structure perfonwt one or more of the following functions: pre venting the part of the wet ceramic greenware body in contact with the carrying structure from deforming;
allowing one or' mare dry hl fluids to contact the part of the, wet ceramic gr'eertware body in contact with the caatryaing structure; and allowing any liquid carrier exiting the wet ceramic greenwate body to move away from die wet ceramic green ware body.
[OO27 The carrying structure Consists of one ear more carrying sheet"." ill one etnbodirnent_ in another embodiment. the carrying structure comprises, one or more carrying;
sheets and one or more support sheets. The one,, or more carrying sheets function to directly contact and support the wet ceramic greuimaame body during the liquid carrier removal process. Preferaably only one cany'ing sheet is utilized. '. he one or more support sheets function to support the carrying sheet in manner that the wet ceramic- body retains its shap , dos not deform, during the liquid carrier re :oval process. The onto or more support sheets mays perform one or more of the following additional functions: facilitate contact of the drying fluid with the wet ceramic ogre :nwaare body, facilitating flow of liquid.
carrier aal~way from the ceramic. greenware body, and facilitating the carrying the wet ceramic greenware body through processing steps, Preferably, the carrying; struct.Llre contains one sulyportshoet, Retains its shape, or does not defon-n, means that the wet ceramic grmnware body does not change :in shape and the portion of the wet ceramic. body in contact with the currying structure remains substantially planar. In one embodiment, retain its sha ?E , or does not i t fi~i'F}}., me am tl}at: the wet ceramic greenware body portion itt contact with the carrying structure does not dimple during the liquid carrier removal process.
[0028] The carrying sheets have two opposing f -aces parallel to care another Which are pla naar, flat. Located between the faces is a series of interconnected walls pelp?Endicular to the two faces. The wails form flow passages which traverse the thickness of the carrying sheets and are, ripen on both faces. The flow pass ge allow fluids to pass frE none face to the other face and thereby through the carting, sheet. The walls have a thickness sufficient to provide structure to the Carrying sheets. Thickness in reference to t N,, walls refers to the dimension of the walls in the direction parallel to the faces of the carrying sheet. The thickness is chosen such that the carrying sheet retains its shape under conditions utilized for liquid carrier rernovaal. Preferably the walls have a thick-ti ss of about 0.l num or ;ri-ater, more preferably about 0.2 mrn or greater and most preferably about r<. 3 miry or greater.
Preferably til wills have a thickness of about 1.0 rtiraa car less, more preferably about 0.5 nun or less and most p:refe aisly about 0.3 trim or less. The walls are interconnected. in at manner such that under liquid carrier conditions the wet c ramic greenwure body retains its shape, does not deform, under liquid carrier removal conditions. In a preferred embodiment, the walls form a repeating pattern, such as as series of regular interconnected s napes, Preferred shapes include ovals, circles, regular polygons and the like. More preferred shapes are circles and hexagon"'.
In the embodiment wherein the shape is a hexagon, the pattern visible from 0-w perspective of either face is a honeyconA) pattern. 'l'ine area of the flow p assaFges from the perspective of each face Of the carry inn, structure is selected such that the :flow Of fluids Fl rough the car ring.
structure facilitates contact of the drying fluid with the wet ceramic, g reenwaa ; . body and removal of the liquid carrier from the vicinity of the wet Ceramic ;reenwaare body. Preferably the area of the flow passages .from the perspective of the faces of the carrying sheet is about fi0 percent or greater and more preferably about 70 percent or greater.
Preferably the area of the flow passages from the perspective of the faces of the carrying sheet is about 99 percent or less, more preferably about 95 percent ci:r less, even more preferably about.
90 percent or less and most preferably about SO percent or leas. The dimensions of the flow pass age}, distance between the walls, are chosen such that the wet ceramic greenware bodies retain their shape, do not de rm, under liquid carrier removal conditions. If the dimensions of the flow passages are too large the portion of the wet ceramic reenware. bodies in contact with the face of the carrying sheet can sag into the holes and perm aanently deforns. The stress introduced can contribute to ,racking and defects in the ceramic õieenwaare bodies. The distance between the Walls of the .flow passages, the sire. of the flow Passages transverse to the flow and parallel to the faaoce of the carrying structure, is preferably about 6 mna of less, more preferably about 4.5 mitt or less and most preferahl.y about 3.5 mrn or less. The distance between the walls of the flow` passages, the size of the flow passages tt'ansvers to the flow and parallel to the fac . of the Catrting structure, is preferably about 1 t:nm or greater and ta-test:
preferably about 15 1111n or greater. The carrier sheet can be prepared from any material that facilitates fort nation of the desired structure and which does not lose its shape, or deform, under conditions for liquid carrier removal. Glass, cer=a iic.. and composite rn ~ferials can be used in eort,;unction with the present invention so long as the materials can be processed such that open pathways can be created transverse to the plate thickness direction (e.g. honeycomb type) in order to fulfill require:rtae-rit for airflow through the support plate thus enabling the drying of wet, green (unfired) -filter parts. With regard to the drying support plate embodiments of the present inventiori, classes for additional materials selection may be selected from glass, ceramics, and c.c,rtaposite . or comprised of any combination of the atlf?tc iai.atttitytaecl classes including plastic and à of merit. mate ials. This is because such materials offer specific, factors including, but or not limited to, impact strength, rigidity, .heniic:atl durability, ekvatcd tettxp rafrirr.. stren4th and processability.. The carrier sheet preferably comprises a. polymeric-material glass, ceramic material, c,_>mpo.ite. , blends, alloys or two or rayon; of the described materials.
(0029] Pt efer-ably the carrier sheet. is composed of a mate rial that has properties that rnatc:b these criteria. pr>. ferably, the material has a combination of heat distortion temperature, as determined by ASTM 0648, and flexural modulus as determined by ASTI 10'790, such that the carrier sheet retains its shape, does not defortam, under liquid carrier removal conditions. Pieforably, the material has a heat distortion temperature tat 0,45 M.Paa load), as determined by ASTM 0648, of about 163 'C or greater and more preferably about 204 "C or greater, Preferably. the material liars a heat distortion temperature (at 0.45 111f'at load), as determined. by AST NI D(48. of about .232 "C or less, and more pre:fe:rahly about 218 "C or less. Prz;.ferably, the. material has a modulus, as deterndried by ASTM D790, of about 2.5 -;Pa or greater anti more preferably about 3.0 GPa or neater. Preferably, the material has a modulus, as determined by AST.lsrl 0'`/90 of about 3.5 Pa or loss and more preferably about 3.3 ON or less.
[0030] Where the carrier sheet is composed of a polymer, preferably the à olym er is a poly tit>Yr titatde, polysultono, her remtcucod nylon., peal ethic suifone, polycarbonate, poly=pine ta:ylerie ether; blends or alloys thereof, and the like. Pt of enable polymeric materials include but are not limited to, polyptithalate carbonate (e g., Lexan from.
General Electric,) a high heat pulycatrbonat , polypheny lsulfone polymer (e.g., Radel R available from Solvay), pcslyothertulfo>ne :Raadt l A available from Solvay", polypÃÃenylcn ether (e, g., SA131C
PIN)), transparent amorphous tlae ra~toplaa tic polymer (ex,, sulfbne polymers sold under the trade name Supradel polymers available from Solvay'), and i;~tatÃ?ia attons, blends, and/or alloys of two or more of the above. More preferred polymeric: materials include polvether bride polysulfone. fiber reinforced nylon, pol ethe.t sulf:me, blends or alloys thereof, More preferred polymeric materials are polyether insides.
[0031] Composites useful for the carrier sheets include polymeric matrices of one or more thereto et or thermoplastic materials having dispersed therein reinforcing fibers or minerals. Preferred reinforcing fibers include glass, carhaortn fibers, natural mineral fibers, graphite fibers and the like. The reinforcing material may also he any natural mineral having a platy structure or high aspect ratio. Such minerals are well known in the art.
Preferred composite systems for use in connection with the Present invention, include high melting reinforced semi-crystall:rnc: polymers, such as, syodiot Ãc_tic polystyrene reinforced With ;class, minerals or combination thereof (e.g.. Idemitsta _X. arec), polyethylene:
uerephtbajatu reinforced with slasss, minerals or aa. combination thereof fee.. Dupont Ry.nite ), polz-phenyfenc: sulfide reinforced with glass, minerals or a combination thereof Portron), liquid crystal polymers (e. g., Celanese Ticona, DePout Vectra, .X-ydar pole ii-ters front..
Solvay), reinforced with ; lass, minerals or a combination thereof, Nylon or polyamide copolymers (0&Zytel and enite from DuPont, A.rrmodel from Solvay), reinforced with gla s, mineral,,; or a combination ther.of, polyester reinforced with glass, minerals or a combination, thereof, graphite thermoset composites, and random fiber composites With polycolettn mrmatrices.
[00321 Preferably the ceramic materials .include aluminum oxide call grades) aluminum nitride, cordierite, fbsedd silica, glass cer artiids, magnesium oxide, mullite, mullite/c:ordierit.
mixti-fires, silicon carbide, silicon nitride, zirconium oxide, and the i.ike_oree Preferred ceramic materials include aluminum oxide and rnulfite/cc rdierite mi.x.tures.
[0033] Where the oven used in the process for removal of the liquid carrier is a microwave overt, the material used. for the carrier plate is preferably microwave transparent.
Microwave transparent material is defined as a material that does not couple at the Spectrum of microwave frequencies and therefore does not heat when used in a microwave drying application, Any high temperature resistant material Which exhih:its low energy absorption in the radio frequency range may be ~ased for the purposes of this invrentioa. By low absorption, it is meant: that the carrier plate material absorbs little, or no energy in the radio frequency range. In a particularly preferred embodiment, the carrier plate absorb less than 2(1 percent, more preferably, less than 1.0 percent of the energy in the field. Preferred microwave transparent materials include of nonpolar amorphous materials as well as nmipolar reinforced somi-ervstalfine materials. Additionally, for con.ec:ticirt drying applications', polar high temperature plastic and/or polymers (i.e., thermosetting epoxies), glass, ceramic, and composites 6.e.' epoxy composites) can he included as materials for rise- in connection with the present invention, [OO34 The carrier sheet has a thickness as measured from one opposing face to the other opposing face such that the face of the carrier plate in contact with the wet c er aartic akreeertwaare body retains its' planar shape., does not deform inner liquid cacri r rem oval conditions. A
suitable thicknes is dependent upon whether the carrier sheet is self supporting or disposed on a support sheet. If the carrying sheet is self supporting it may need to be thicker tha : if a support sheet is utilized, alternatively the carrying sheet. may. be thinner is ;3 support sheet is utilized, Generally, tyre thickness of the Carrying sheet is preferably about 1.0 c as or greater, more Preferably about 1..~ cm or greater and most preferably about 2,0 cm. or greater.
Generally, the thickness of the carrying sheet is preferably about 4.0 era or lest and most preferably about 3.0 cra or less. Where the carrying sheet is used without a support sheet, is self stupportin;. , the thickness o' the carrying sheet is, preferably about 1.5 cm or greater mid most pa e ferably about 1.75 crn or greater. Where the carrying, sheet is used s4 ithout a support.
sheet, is self staff>porting, the thickness of the carrying sheet is preferably aabout 4.tl cart or less, more preferably about 3.0 cm or less and most preferably about 10 cm or less.
W 'hy re the carrying sheet is used with aa. support sheet, the thickness of the carrying sheet is preferably about 1.5 cm or greater and most preferably about 1..75 cm or Mgreater, Where the carrying sheet is used with a support, sheet, the thickness of the carrying sheet is prefer ably about 3,0 Cal or less, more Preferably about 2.5 crag or less and most preferably about 10 agar or less. It is a combination of features which facilitates the carrier sheet having the property of retaining its shape under liquid removal conditions. The carrying sheet thickness and the heat distortion temperature and the modulus of the material from which the carrying sheet is fabricated ate important vamiables..Aso relevant is whether a support sheet is utilized. One skilled in the art is capable of balancing these Criteria within he defined Parameters to achieve the desired stiffness under liquid. removal condition. The carrying sheet: has one or n%-ore outer edges;.
depending on the shape of the vat-tying sheet from the perspective of the opposing faces. '1'h0, shape can be any shape. which allows the, Carrying to curt to support a wet ceramic greenware body while exposed to liquid carrier removal conditions. Preferably the shape of the carrier sheet from the. erspecti'-tÃ: of the t:wo opposi:ng faces is round, oval or polygonal. More Preferred. shapes are round, oval rec tangulaar (including square) or hexagonal, [0035) In the embodiment wherein the carrying sheet i utilized without a support sheet, the carrying sheet can include features which enhance its desired function.
Among such features are molded edges on the sides perpendicular to the two opposing faces, indexing.
tic>la_ in the c.cfse or in the comer of the carrying sheet. (for instance drilled in the corner of a honeycomb), and the like. Such features can be incorporated utilizing procedurees well known to those skilled in the art.

00-36) The support 4heet. when utilized, functions to suppti -t the carrying sheet, prevent the carryi.ng sheet from deforming. facilitate colitact with the d in fluid w ith the wet t e:raniic area nw'are body; functions to carry the carrying sheet with the wet ceramic {greemsware body disposed thereupon through one or more processing steps (for instance tliri:>ii. h the clryh ; process) andio.r facilitate removal of the liquid caarriet- from that vicinity of the wet ceramic greenware body; during the liquid carrier removal process. The support sheet exhibits 'sufficient stiffties to allow= the c ut'ry ng Sheet to retain its shape during= the liquid carrier removal process. no support sheet also has sufficient open area in the direction parallel to the face,, of the carrier sheet to allow transport of the drying fluid and liquid carrier through the support sheet wad the Carrier sheet. Typically,, the support shut comprises a sheet of material which meets these criteria. Such sheet prefer ably has two opposing faces parallel to one another and a thickness sufficient. to provide stiffness to the carrying sheet. Preferably the support sheet has a thickness, measured as the distance from the two opposing faces, of about 0.5 carp or greater and more preferably about 0.8 cart or greater.
Preferably the support sheet has a thickness, measured as t c, distance .from the two opposing laces, of about 2.0 ctn or less; :ti ore preferably about 1.5 cm or less and most preferably about 1.2 Cal or less, Because the support sheet: does, not Contact the wet ceramic gteenware boc_ly, the support plate does not have a restriction on the size of the opening. s transverse to the two opposing faces of the support plate. It is desirable that the support sheet have is much open space as possible to facilitate the transport of fluids there tht-ouf h. Preferably the area of the openings in the supp{.tit sheet from the perspective of the faces of the support sheet is about 60 percent or greater anti raiore pr ferablyr about 70 percent or gteate..r. Preferably the area of the openings in the support sheet :fr=om the perspective of the faces of the support sheet is about 90 percent or less and more preferably about 80 percent or less. The support sheet can comprise any material that provides the recited limpet' ies. Preferably the support sheet Comprises a polyirrer, trior'e preferably a polymer as described above as useful for the carrying sheet.
Where the over, used in the process fcrr removal of the liquid carrier is a.:niicr'owave coven, tile polymer used for the support plate is pre -uribly microwave: transparent.
Preferably the support sheet has a recess adapted for seating the carrier sheet on the support :sheet, Preferably the support sheet comprises a. means for cooperating with a conveyor system to retain the carrier structure in the proper location on the conveyor system and facilitate movement of the Cartier structure along the con-veyor. Preferably such means includes indexing holes on the support structure which rrmatch mating protrusions or structures on the convey=or.
[007] The support slice! preferably has a raised portion -bout the periphery of one face, preferably the face that a carrying, sheet is placed on, wherein the raised portion defines a recess from the plane defined by the raised portion. Preferably the support sheet has a ledge Ii for holding the carder sheet in place which defines a plane below the rased portion and the Cenral part of the support sheet, and preferably in a manner such if-tat the carrying sheet is raised above the face of the center of the support sheet so that the fluid can flow between the face of the support sheet and the carrying sheet and out through the passafges ill the carrier sheet. The ledge can be inset in the recess of the support sheet adapted to support the carrier sheet. In another embodiment the ledge can be a separate part that is inset into the recess of the support sheet, in this embodiment the ledge insert can he prepared f'r'om any mate-riaal useful as the support sheet. In embodiments rchete. the caany,ing sheet is self sul potting, a support sheet may be utilized to facilitate moving the wet ceramic ggyeenwam body through processing. In this e:nmhadimnent the center of the sheet can be open with a ledge sufficient to hold the carrying sheet in pÃace:. ?alternaatively, the support sheet can have holes in the area surrounded by the ledge. In this embodiment t:he ledge needs to have sufficient thickness transverse to the face of the support sheet to create an air gap bets een the support sheet face in the center a and the carryings het so that fluid can flo v to all of the passages in die CEUTying sheet not ra thing in the ledge. This is to facilitate the flow of drying fuid through all of the passages not resting, in the hedge. In the embodiment wherein the carrying structure is not self supporting the support plate needs to have sufficient points of contact with the car'r'ying structure to keep the carrying plate flat. In another embodiment the carrying sheet Can be lart e enou gh to set on the raised portion about the periphery of the support sheet such that the r'eces hems an air gap that allows Ãhc drying fluid to flow into the air gap and to and through the passages in the carrying sheet.
[0038] The method of the invention for removing liquid carrier from a wet ceramic menware body involves placing the wet ceramic body on a carrier structure and placing the wet cc ramic greet_twaare body on the cat-rier structure in an oven under conditions such that the liquid carrier is substantially removed from the cerm-nice greenw tre body. in one embodiment, cane face of the wet ceramic greel-miare body is placed on carrier structure.
This process is generally utilized when the wet ceramic greenware body has an irregular c Mass section. l ahape, that is without a planar surface. that can support the wet ceramic greenware body on the carrier plate or when the wet ceramic greenware body has a circular or oval cross-sectional shape, In another' embodiment, a planar surface of the si c t ceramic greenware body having a planar surface from the perspective of its cross-sectional shap , has a flat outside surface, is placed on the carrier structure. This is used when the wet : er'ami gra'enwaare. body ha a cross sectional shape with a. planar surface that can support the wet ceramic gree.:nware body on its side, for instance when the ceramic grecnwaare body has a polygonaÃ., preferably rectangular, crass-section.

(0038] Any= oven which assists in rrtncoitig the liquid carrier from the wet ceramic body may be ufllix cl in this method. Among: preferred ovens useful in the invention are MIVection.
itrfr ared, microwave, radio frequency ovens and the like, in a more preferred embodiment a microwave oven is preferred. The wet ceramic body on a carr'ier structure may be placed in an oven for r sufficient time for the liquid carrier to be aubstantial.ly removed from the ceramic `Meerrware bc#d axed then removed from the oven. The wet ceramic body on a carrier structure can be manually placed in and removed from the oven. Alter2 .at.ive_fy the wet ceramÃc bodya o n a carrier structure can he utomatic'ally introduced and removed from an oven.Arty automatic mean` for introducing a part into and removing a part from an oven may be utilix.ed. Such teams are well known in the art. In a preferred embodiment, the wet ceramic body on a carrier sumuctur is placed on a conveyor and passed through one or more ovens on the conveyor. The residence time of a wet ceramic body on a s. riri r tru ttirC in the one or more Owens is Chosen such that under the conditions of the one or more ovens substantially all of the liquid carrier is vennoved. The residence time is dependent upon all of the other conditions, the size of the wet ceramic greenware structure and the amount of liquid carrier to he removed. The tentipcraature that the wet ceramic body on a carrier structure is exposed to in the one Or More Ovens is chosen to facilitate: the removal of the liquid carrier from the wet ceramic body. Preferably the temperature is above the boiling point of the liquid wrier and below the softening rE #21per'aatu e of mat r'ial from which the carrier structure is fabricated and the temperature at which any, of the ceramic precursors decompose. Preferably, the temperature that the wet ceramic body ofi a can ier structure is exposed to in the overt is about 6.0 'C or greater, more preferably, about 80 C or greater and most preferably about 100 "C or greater, Pr fembly. the. temperature that the wet ceramic body on a carrier' stnicture is exposed to in the oven is about 120 `C or less and most preferably about 110 "C or less (0040] The. ,Yet ceramic greerlwware body in the overt is preferably contacted with a drys Ãn ; fluid of a vacuum is applied to the oven to facilitate removal cif liquid carrier from the wet ceramic bodya..T''refer:ably, the wet ceramic greenware body is contacted with a drying fluid. In the embodiment, wherein the wet ceramic greenware body is shaped as the precursor to a flow through filter, wherein the flow passages in the wet ceramic gieenwaae body have not been plugged at one end, it is pre fe:table to flow the drying fluid through the flow passaga.s of the wet: ceramic mew ne. body. This is f rciitated by d irectitng the drying fluid to .flow in the same dire .tion as the flow passages are disposed on the carrier structure.. i one face of the wet ceramic gree:nwaare body is disposed on the. carrier structure, the drying fluid is directed up through the carrier structure in the direction of the wet ceramic greenware body so that the dr~yin l fluid passes into and through the flow passages in the wet. ceramic gr enware body.
Where the wet ceramic. green ware both has a flat planar side and the wet ceramic p:r'eenware body is disposed on the carrier structure on its fiat planar side, the flow of the drying fluid is directed to flow through the ffo passages in the wet ceramic greenwar body. In the.
embodiment whe .tein the wet ceramic teen are body on the Carrier Structilre is passed through one or n:#;: re ovens on a ea:n'Se 'or, wet ceramic green ware bodies are dispoied such that the direction of the flow passages arc transv r e to the direction of the conveyor and the drying fluid is passed in a direction transverse to the direction of the convey-or such that the drying fluid passes through the flow passages of the wet ceramic greenware bodies. The _ dr iy ng:fluid can be any fluid which enhances the remove nl of liquid carer from the vicinity of the wet ceramic. <greenware body. Preferably the do ing fluid is a ua .
Preferred gasses include air, ox zen, nitrogen, carbon dto tdc., inert gases and the. like, ,Most prLtlnhly the der-,i.ng fluid is air. After the drying fluid is contacted with the wet ceramic greenware body it is removed from the vicinity Of the wet ceramic greenware bodyr along: with the liquid carrier entrained in the dr'yin ; fluid. The flog=w of drying fluid. is generated by any means which facilitates to ovean-ent of a drying fluid such as a pump, a blower, and the like. The flow rate of the drying., fluid is chosen to facilitate the removal of liquid carrier from the Vicinity of the. Wet ceramic greenware body. The preferable flow rate will vary depending on a variety of conditions..Determination Of a N. Uitztble flow rate is within the ability of one skilled in the art.
Preferably the flow rate is about 1000 en. mt l-t (cubic tn7et:: a rnc~tnr, or greater and more preferably a about 1650 cu. r Y01 or greater. Preferably the flow rate :is about 20(X) c u.m/h Or less and more preferably about :i6 () cu. tr:t/h err. less.
[0041] Other important parameters for drying ceramic, parts that are afforded utility by the carrier plate of the present invention ar : two frequency #egnrre s of microwave power (2.45 G.Hz and 915 MHz), varied reflected powers ai:t there frequencies (from.
about tl to about 100 %), relative humidity that can vary from about 0 to about 100t ., t widen e. time that cat) vary from about 0.01 to about 10 hours in periodic oven or belt dr-i 'en continuous ovens, and a maximum part te.n:nperaw.re that can range from about 50 to about 14f:t' C.
[0042] After removal of the liquid carrier from the, wet ceranmic gteeriware body, the ceramic rreenware body can be prepared for conversion to a ceramic body and converted to a.
ceramic body. In the embodiment wherein the ceramic greenware body is a precursor to a flow through filter, every Other flow passage on each end is pltugged, preferably with shapeable ceramic greenw r , wherein each flow passage is open on one end and eacl-.t flow I-`rn '#ge that is upon on One face has plug d glow passages <ld1 Trent to its Open pa m PI
Thereafter, the ceramic greenware body is exposed to conditions to bunt out the binder and to form the ceramic. structure. Pro eesses to achieve this, are well.known in the all.
(0043] Figure 1 is a drawing of the conventional carrying sheet 10 showing one of two opposed faces 1 i , a plurality of 1 cm holes 12 and plastic material. located ber sveen the holes 13. .r is a aho n are indexing holes 14 for orienting the carrying sheet 10 on a conveyor belt, not shown in .Figure I , Figure. 2 is a cut away view, of the prior pct sheet taken along lire.. 2-2.
The view is perpendicular k s face I :l along, the designated Tine. Figure 2 shows the cart-ying sheet 10 and the edge of the two faces 11. Also shown are the holes :12 and the material located between the holes 13.
[OW] Figure 3 shows a carrying, structure comprising one embodiment of a support sheet 20.. Figure 4 shows a cut away view of the support sheet along line 4-4 which is perpendicular faces 21 and 27. The support structure has two face,,,, a top face 21 and a bottom face 27. Located in the center portion of the support structure 20 is a plurality of holes 22 having, material located about the holes 23, The support structure has a recess 25 located in the top face 21 of the support structure 20. The recess 25 is defined . by a raised section 29 di .posed about the periphery of the top face 21. of the support sheet. About the.
periphery of the recess is a ledge 26, The ledge 20 functions to hold a carrying sheet 28 above the portion of the recess 2S in which the holes 22' are located so as to form an air gap 38 such that a fluid, ti xr example a it, can flow along face 21 :inside of ledge 226 and through all of the carrying sheet 28 not resting, on ledge 26. Also shown seated on the support structure 20 is a carr ring sheet '2$. in particular the carrying sheet 28 rests on the ledge 26 such that there is an air gap 38 between. the caartrving sheet 2.$ and the. top face 21 of the support structure 20 which is surrounded by the ledge 26. The air s sp 38 is sufficient to allow a fluid to flow along the central portion of the support structure 20 and through the portion of the caacrving sheet 28 not resting: can the ledge 26. TI-te support structure 20 also h=as located at each corner of the structure indexing holes 24 adapted for matching with posts on as conveyor belt to hold. the structure. in place on a conveyor belt while. the structure is passed through all oven as described herein. The carrying sheet 28 has a honeycomb structure with two faces 30, a plural=ity of walls 3 land holes 32 which define a hexagonal pattern of a honeycomb structure. The walls 31 and holes 32 of the carrying sheet are. pet ?eiidicular to the face 30 of the carrying sheet 28 and adapted to set perpendicular to the face 21 of the support structure.
[0045] Figure 5 shows a second embodiment of a support structure 20 with a carrying sheet 28 shown above the support sheet 20 and arrows showing where. the carrying sheet 28 rest=s on the support sheet 20. The significant difference f om Figures 3 and 4 is that the center of the support sheet is removed and the ledge 26 is circular in shape forsnin a circular openi=ng 29 in the support sheet 20. Figure 6 shows a cut away along, line 6-6 which is perpendicular to faces 21 and :''7. Fi ,-ure. 6 also shows a carrying sheet 28 above the support sheet 20 and where the can,y ing sheet 28 rests on the support sheet 20. The, carrying sheet 28 rests on the is dge- 26 in the recess 25. The carrying sheet 28 and the top face, 21 of the support is sheet 20 f ant an air gap 38. Arrows are included which show the flow of a.
drying fluid front blow the support: sheet, to the passages in the carrier ,het 32.
[0046] Figure 7 shows a view of a carryin ; sheet. 28 disposed oia a support structure 20 of the first embodiment from above the car ;r'ing sheet looking down through the carrying sheet to the support structure., Shown is the ledge, 26 on which the carrying sheet 28 rests, Also shown is the face of the carrying sheet 28 with the walls 31 and holes 32 forming a honeycomb structur'ce. Also visible below the carrying sheet 28 are the plurality of holes '22 and material 23 between the plurality of holes 22, The raised portion 39 of the face 21 of the support sheet is also shown. Figure 8 is a similar view of a carrying sheet 28 above to support shed 20 of the second embodiment, The carrying sheet 28 is supported on t 26 which is circular which form" an open area 29 in t:he center of the support sheet 20.
[0047] Figure. 9 shows a support sheet 20 of the first embodiment in relation to a conveyor belt 33 having posts 34 adapted for the indexing holes 24 of the support sheet to set.
upon. The posts 34 hold the support sheet 20 in place on the conveyor belt 33 while t:e support sheet and carrying sh, et with a wet ceramic r reenware 1roc1 ?f>
place. on the t errs ing Sheet. is pa isaed through processing steps, such a through to drying oven.
Figure 9 shows a.
carrying sheet 28 above the support sheet 20 with arrows showing where it would rest on the support sheet. 20. Also shown is a wet ceramic lgreenware body 36 and where the. body 36 is to test while being passed through an oven ia~ute 9 also shows a fan 35 adapted :for passing air to and through the support sheet 20, the carrsing sheet 28 and the wet ceramic reen as body 36, Figure 10 is similar to Figure 9 except the carrying sheet 28 of the second embodiment is used. In both embodiments I and 2 the carrying sheet 28 is self supporting and the support sheet primarily- functions to facilitat:. movement of the wet ceramic body on a convenyor beat through processing, [0048] Figure ;l 1 shows the first embodiment of a support sheet having a ledge in the form of an insert 37. The arrow shows where the itisert,17 sits into the.
carrying sheet 20 on its top face 21, Figure 11 shows the insert 37 is set inside_ the raised portion. 39 of the face . 21 of the support sheet. Figure 12 is a. cutaway of Figure 1 1 along lines 12.-12 wherein the cut shown is perpendicular to face 2l . Also shown is a carrying sheet 28 set in the recess 25 on ledge 25 to form an air gap 38. An arrow shows the flow of fluid through holes 22 into and through the air gap 38 and to and through the, passages 32 in the carrying sheet 28. The insert 37 can be used with a support sheet wherein the center of the sheet is open as shown in embodiment 21 see element 29 Figures 5 and 6. he insert can be of wiy shape:
that raises the carrying sheet and which allowws fluid flow to the:. aw'et ceramic grec nw ire body:
(0049] Flgur 13 shows another embodiment wherein the carrying sheet 28 is placed on the raised portion 39 about the.. periphery of the face; 21. of the support sheet 20 such that the recess 2~ forms the air gap 38 that allows a drying fluid to flow tà ereffi ougÃa and to the passage 32 in the ceramic sheet 28.
SPECIFIC EMBODIMENTS OF INVENTION

[0050] The following examples arc included for illustrative purposws only and are not intended to limit the scope of t e..inv=ention. Unless otherwise stated, all parts and pc rc enta es a are by weight.
[00511 Example"
[0052] A number of wet ceramic (mullite precursor) green ware bodies are prepared. as described in US Patent 6,963,554 (incorporated herein by F elerence:). The wet ceramic bodies are either placed on a conventional carrier plate, as shown in Figure 1 and 2, or a carrier structure of the invention, as shown in Figure 5 and 6 and passed through an oven as described herein after, The conventional carrier plate has a dimension from.
the perspective Cof the opposing faces, 24.76 czrx x 24.76 c.rn, with a thickness of 1 crn, machined from a poly uiphone plate with 195 holes of 1 cm diameter and spaced by 0,5 and 1.0 call of walls of solid pt lysuiphone. Together the two plates Of the support phate. aaucà the carrier plate (sheet) comprise the carrier :stn ictta_m,. The support plate. is: additionally characterized by having two different level recesses Machined into the plate (shallow and deep): the shallow recess: is intended to hold the carrier plate of the invention, Whereas the deep recess serves the function of delivering drying fluid and acts like a plenum for delivery sideways and upwards to the ceramic waxe.. The deep recess is machined with large di. ammeter holes (2. cm in diameter) with 1 cart solid bridging material (walls) be: t:ween hole.' Which afford rigidity to the entire assembly. A carrying plate of the invention has a dimension from. the perspective of the opposing faces, 24.76 cm x 24.76 cna, with a thickness of 2 cm, and ce>Aaa1?nisi s a tftc rraac?plastic. ltcxa3e %ereaaaÃ> sheet (if a Ã>oÃyetfleri mde. honeyconih of 0.35 cm cell diameter with wall thickness of 0.02 cm, The. polye.ther inride he neyc aaanb structure is availabÃe, from Tuhus Bauer, under t e trademark Ultern", (0053] Wet gr ee:nwaa_re ceramic. honeycomb filters are placed alternatively on top of Conventional plates and carrying structures of the invention on a dryer conveying N belt. Wet extruded honeycomb ceramic grccnwaare parts for the tests are nominally 2,500 grams in weight, 2Ø32 cm in diameter, and 15.4 cm high. Cell density is nominally 200 CPT (cells per square inch.). Starting tna.caistur content is nominally between 27 and 31 percent, The wet extruded honneyrcolub ceramic,, gr enwaare, parts axe placed on the carrier plates with one face having the.. end of each flow channel placed on the carrier 1>laate s. The carrier structures are placed on a conveyor and passed through an oven and exposed to temperatures of about 6-5 to about I (K) "C with air blown from below the conveyor into and through the flow passages :in a7' the wet extruded honeycomb ceramic greenware parts. The residence time in the oven is about 4: minutes. Over a period of 4 months approximately 500 parts are dried us ng carr'ier structures of the invention and only 2. percent of such parts show cracks or def nts on the surface: and approximately 500 parts are dried using the conventional carrier structures any 90 percent of such parts show cracks or defects on the surface.
[0054] The preferred embodiment of the present invention has been disclosed. A
person of ordinary skill in the art Would realize hors'ever, that certain modifications would come Within the teachi_n4as of this invention. Therefore, the following claims should he studied to determine the true scope and content of the invention. Artnumerical values recited in the above application include all valucs from the l stir values to the upper value in increments of one unit f mvided that there is a separat_ion of at least 2 units between ariy lower ,value. and any higher value, As an example, if it is stated that the- amount of a con component era value of a process variable such as, for example, temperature, pressure, time and the.
like is, for example, from t to 90, preferably from 20 to 80, more, pref"erai?1y from 30 to 0, it is intended that values such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 etc. are expressly enumerated in this specification For values which are less than one, one unit is considered to he 0.0001. 0,001, 0,01 or 0.1 as appropriate. These are only examples of what is specific ally intended and all possible- combinations of tax me:r cal values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this al)plication in a similar manner.
ll'rrless otherwise stated, all ranges include bod--t endpoints and all.
numbers between the endpoints. The use of "about" or "approximately" in connection with a range applies to both ends of the range. Thus. "about 20 to 30" is intended to cover "about 20 to about 30", inclusive of at least: the, .specified endpoints, Parts by Weight as used herein refers to compositions containing 100 parts. by weight, The disclosures of all artir les and r"4erences, Including patent applications and publications, are incorporated by reference for all purposes'.
The term ";consisting essentially of" to describe a combination shall include, the elements., in.redieents, components or steps identified, and such other elements ingredients, componnts or steps that do not materially affect the basire- and novel characteristics of the combination.
The use, c& the terms "comprising" or ":including" to describe combinations of elements, ingredients, components or steps herein also contemplates embodiments that consist:
essentially of the elet}gents, ingredients, Components or steps. Plural elerrrents, in r'ents, components or steeps can be provided by a single integrated element, ingredient, component or step, r .lternativel , a single integrated element, ingredient, component or step might be divided into separate plural elet lenÃs, ingtediernts. components of step. The disclosure of "`.a"
or "one" tode`cribe an eletrient, in-r' dient, component or stop is not intended to foreclose additional elements, n,greedients, cmrtponents or steps, I

Claims (16)

1. Claim 1: A method comprising a) placing wet ceramic greenware body on a carrying structure, and b) exposing the wet ceramic greenware body to conditions such that a carrier fluid in the ceramic greenware body is substantially removed;
   wherein the carrying structure contains a carrying sheet comprising a material which retains its shape under drying conditions comprising one or more polymeric materials, glass, ceramic materials, composites, blends, alloys or mixtures thereof, the sheet having two flat parallel faces and a plurality of walls perpendicular to the flat parallel faces wherein the walls form a plurality of flow passages communicating between the two faces, the largest distance between any two walls in the carrying sheet is from 1mm to 6 mm and the walls have a sufficient thickness of 0.1 to 1.0 mm to support the wet ceramic greenware body under drying conditions without deforming and the area of the flow passages measured parallel to the two faces is from 60 to 99 percent.
2. Claim 2: The method according to Claim 1 wherein the carrying sheet comprises a polymeric material which exhibits a heat deflection temperature of from 163 C°
   to 232 C and a modulus of 2.5 to 3.5 GPa such that the carrying sheet does not deform under drying conditions.
3. Claim 3: The method according to Claim 2 wherein the polymeric material comprises polyether imide, polysulfone, fiber reinforced nylon, polyether sulfone, polycarbonate, polyphenylene ether, blends or alloys thereof.
4. Claim 4: The method according to any one of the preceding Claims wherein the carrying structure comprises a carrying sheet having a thickness of 1.0 cm to 4.0 cm which is sufficient to prevent the carrying sheet from deforming under drying conditions.
5. Claim 5: The method according to any one of the preceding Claims wherein the carrying structure comprises a carrying sheet on a support place wherein the support plate has sufficient stiffness under drying conditions to prevent the carrying sheet from deforming under drying conditions.
6. Claim 6: The method according to any of the preceding claims wherein the wet ceramic greenware body on the carrying structure is placed on a conveying means and passed through an oven and exposed to elevated temperatures sufficient to dry the ceramic greenware part.
7. Claim 7: The method according to any of the preceding claims wherein a drying fluid is passed over, around and/or through the wet ceramic greenware body during drying.
8. Claim 8: The method according to any of the preceding claims wherein the polymeric material of the carrying sheet is transparent to microwaves.
9. Claim 9: The method according to any of the preceding claims wherein the wet ceramic greenware body is a flow throw filter having two opposing parallel faces and a plurality of channels communicating between the two faces.
10. Claim 10: The method according to Claim 9 wherein the drying fluid flows in the same direction as the channels in wet ceramic greenware body and flows through the channels.
11. Claim 11: The method according to Claim 9 or 10 wherein the cross sectional shape of the wet ceramic greenware body is round, oval or irregular and one face of the wet ceramic greenware body is placed on the carrying sheet and the drying fluid is passed through the carrying sheet and the wet ceramic greenware body.
12. Claim 12: The method according to Claim 9 or 10 wherein the wet ceramic greenware body has one or more planar exterior surfaces perpendicular to the direction of the flow passages and one of more of the planar exterior surfaces of the wet ceramic greenware body is placed on the carrying sheet and the drying fluid is passed through the flow passages of the wet ceramic greenware body.
13. Claim 13: The method according to any of the preceding claims wherein, the support structure is fabricated from the same polymeric material as the carrying sheet.
14. Claim 14: The method according to any of the preceding claims wherein the carrying structure consists of a carrying sheet having a thickness of 0.5 cm to 3.0 cm and a support structure having a thickness of 0.5 cm to 2.0 cm.
15. Claim 15: The method according to any of the preceding claims wherein support structure has an open volume in the plane parallel to the face of the carrying sheet of 60 to 90 percent such that a drying fluid can pass through the support structure to the carrying sheet and the wet ceramic structure.
16. Claim 16: The method according to any of the preceding claims wherein the distance between the walls of the carrying sheet is between 2.5 and 3.5 mm.